I'm looking for something sexy for my wife for her birthday? Any suggestions?

Shirlye of Hollywood has lots of great sexy lingerie. They are stylish and super cute. You can see a great selection at http://www.BiggerBras.com (this site carries all sizes. They just specialize in the larger cups). Check out the styles:

http://www.biggerbras.com/catalog/bras-lingerie-swimwear.cfm?ssbrand=47&sssize=&sstype=&sscolor=&sspage=1&stock=1&price=

I personally prefer Fredericks oh Hollywood for all of my lingerie needs. They have a vast selection of items aimed at allowing a woman to feel utterly sexy. The items range in price as do the selection. I personally like bustiers, they are a great item for women of all sizes. This is a direct link to the
corsets, http://www.fredericks.com/corsets/corsets,default,sc.html 

They also have a great selection of over the top, ultra provocative pieces. http://www.fredericks.com/lingerie/seduction-sexy-lingerie/li3,default,sc.html

Also on the site, they have a great selection of babydolls. http://www.fredericks.com/lingerie/babydolls/li12,default,sc.html

All in all, Fredericks has everything for everyone. The sizes range, catering to women of all sizes. They also carry sexy shoes, clothing and their clearance section is EXCELLENT!

I love fine lingerie and I'm sure your wife would appreciate it too!  You can select from bras, panties, boxer shorts, camisoles, tees, robes, slippers and more depending on her style and taste.

I like the Natori and La Perla brand for selection and quality.  Package this with a bottle of her favorite perfume, dark chocolate and champagne and you will be a star!